The present invention relates generally to integrated circuit fabrication. In particular, the present invention relates to a multilayer electrode structure for capacitors in integrated circuits.
In the manufacture of ferroelectric or high dielectric constant capacitors, two single layer electrodes are separated by a dielectric to form the capacitor. Each electrode is made of a single material or composition, such as platinum, aluminum or silver.
All components or devices on each integrated circuit must meet several requirements in high volume manufacturing of integrated circuits. Such requirements include good adhesion characteristics, high electrical conductivity, etchability in plasma, etchability in reactive ion etchers, oriented lattice planes for proper dielectric film growth, resistance to oxidation, resistance to diffusion and low cost. The standardly selected materials for capacitor electrodes, platinum, aluminum and silver, may meet some of these requirements, but do not meet all of these requirements in the many different applications of capacitors in integrated circuits.
Thus, it is a primary object of this invention to provide a capacitor electrode for integrated circuits which meets all of these requirements.